781529 - Use -MMD flag for dependency generation

Status: RESOLVED WONTFIX

(Firefox Build System :: General, defect)

Description

[Mike Hommey [:glandium]]

We currently use -MD -MF file.pp to generate makefile dependencies based on preprocessor output. This includes system headers. We should add -MM so that system headers are not considered. This would remove a lot of file checking.

At the same time, we should consider the headers in $(DIST)/system_wrapper and $(DIST)/stl_wrappers as system headers.

Comment 1

[Mike Hommey [:glandium]]

Attachment: Add -MM flag for dependency generation and treat wrappers as system includes

Comment 2

[Mike Hommey [:glandium]]

Attachment: Add -MM flag for dependency generation

Actually, the -isystem part is not a good idea, as some of the wrappers are actually used for in-tree non-system headers. Using -isystem would make them fail to be used. Just limit to -MM.

Comment 3

[Mike Hommey [:glandium]]

Attachment: Use -MMD flag for dependency generation instead of -MD

Erf, in fact -MM doesn't do the right thing. Replacing -MD with -MMD does.

Comment 4

[Mike Hommey [:glandium]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/a1ba35958b98

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/a1ba35958b98

Comment 6

[Mike Hommey [:glandium]]

GCC sucks.
https://hg.mozilla.org/integration/mozilla-inbound/rev/60a42d321090

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/60a42d321090